Packaging of gas-pressure-generating cartridges



R. WARK Nov. 10, 1942.

' PACKAGING OF GAS-PRESSURE-GENERATING CARTRIDGES Filed Aug. 2, 1939 [20176]? WCUK INVENTOR ATTORNEY Patented Nov. 10, 1942 PACKAGING OF GAS-PRESSURE- GENERATING CARTRIDGES Robert Wark, Irvine, Scotland, assignor t Imperial Chemical Industries Limited, a corporation of Great Britain Application August 2, 1939, Serial No. 287,883 In Great Britain August 8, 1938 1 Claim.

The present invention relates to the packaging of gas-pressure-generating cartridges of the kind in which propellent explosive or other combustible material is present at the end of the cartridge remote from the metal base thereof, and in which the said remote end is closed either wholly or in part by a disc or other closure member of inflammable material, such as Celluloid. Cartridges of this construction are usually intended for forward-venting, and are suitable for the actuation of pressure-operated mechanical devices. They are used for instance to start aeroplane engmes.

Cartridges of this type are usually packed closely side by side in batches in a metal or fireproof box corresponding in depth to the length of the cartridges, and are usually separated one from another within the box by a light framework. On account of the exposure of inflammable material at the end of the cartridge, the accidental ignition of one cartridge in the package is particularly liable to ignite the other cartridges, even if things are arranged with the alternate cartridges in a row upside down.

This invention has as an object to devise a new and safer manner of packing such cartridges. A further object is to devise a method of packing such cartridges whereby the danger of fire is reduced. A further object is to devise a method of packing such cartridges so that should one cartridge accidentally fire, the fire will not spread 'to the other cartridges in the box. Further objects will appear hereinafter. These objects are accomplished by the following invention.

I have discovered that the provision of a light cap of flame-resisting rigid material fitted over the said remote end of each cartridge is sufficient to protect the remaining cartridges in the box from ignition by any one cartridge, notwithstanding the strong deflection by the container wall of the emergent flaming gas stream from the ignited cartridge.

According to the present invention, cartridges of the kind described, when loaded in a package, are fitted with a fire-resisting cap adapted to protect the inflammable head from ignition through exposure to the products of combustion of another cartridge within the package. The cap need not constitute a gas-tight fit, and indeed quite a loose fit is permissible.

The cap may be made of thin metal, synthetic resin or other flame-resisting rigid material and it may be slightly bulged to a suitable diameter so as to prevent accidental insertion of a capped cartridge into a firing chamber. I prefer to employ, in addition to the protective cap, a thin metal partition between the neighbouring cartridges.

The invention is illustrated with reference to the accompanying drawing which illustrates a box with one of the cartridges in position. Referring to the figure, 1 represents the tin plate box with a hinged lid, 2 represents the tin plate separators used to divide the interior of the box into compartments, 3 is a fiat tin plate sheet resting on top of the separators, and 4 is a corrugated tin plate sheet. The cartridge which is seen in place in one of the compartments is constructed of a cardboard tube 5, 1" in diameter and 2 /2" long, with a metal base 6 and an electrically fired fusehead igniter. It contains a charge of 20 grams propellent powder in the form of short rods about 0.3" in diameter and 0.3" long. The end of the cardboard tube is turned over in the usual way on to a thin Celluloid disc which has been placed on the top of a charge. The turned over end is covered by a protective cap 1 made of zinc about 1.05" in external diameter and about 0.016" thick, the cap being 0.4 deep and a sliding fit on the end of the cartridge. The cap is so shaped that the cartridge cannot be placed in the firing chamber without removing the cap. It is usual to pack these cartridges in 20 compartments in each box. It has been found using a box and cap of the above form that the danger of igniting any cartridge is much reduced and that even if such ignition does take place, the fire is confined to one cartridge. Instead of being made of metal and having metal partitions, the box could have been made of a synthetic resin or other flame-resisting rigid material of sufficient strength. Instead of using zinc for the cap, I could have used brass, copper, aluminium or tinplate.

As many apparently Widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claim.

I claim:

A package adapted for the safe transportation and storage of pressure-generating cartridges containing a propellent explosive which comprises a container sub-divided into compartments defined by metal walls extending from the bottom of the container to the top, a plurality of said pressure-generating cartridges disposed one in each of said compartments, each cartridge being provided with a metal base, and on the venting end a non-combustible over sized metal cap non-combustible metal box with a hinged lid 10 of the same material, and a fiat metal sheet disposed above and resting on top of the metal partitions defining the compartments, and a corrugated non-combustible metal sheet resting on top of said flat sheet, the various parts of the assembly cooperating to prevent the ignition of any of the various cartridges from the inadvertent ignition of any one of the number.

ROBERT XVARK. 

